Julia Roberts broke down in tears as she spoke for the first time about the “heartbreaking” death of her half-sister Nancy Motes.

The Oscar-winning actress, 46, said she had yet to come to terms with the tragedy and was taking things “hour by hour”.

Nancy died of an apparent drug overdose in February – just weeks after she blasted her superstar relative on Twitter and claimed they had a rocky relationship.

But a tearful Julia revealed how she was left devastated by the loss of Nancy, 37, and was coping through meditation.

She said: “It’s heartbreaking. There aren’t any words to explain what any of us have been through. It’s hour by hour some days but you just keep looking ahead.”

Julia did not go into the details about their relationship in the interview, which was published this week in US ­newspaper the Wall Street Journal.

But the Pretty Woman star, who was speaking on March 1, just 20 days after Nancy died, added: “You don’t want anything bad to happen to anyone, but there are so many tragic, painful ­inexplicable things in the world.

“As with any situation of challenge and despair, we must find a way, as a family.”

Julia, who converted to Hinduism four years ago, went on: “It’s so hard to ­formulate a sentence about it outside the weepy huddle of my family.

“Meditation or chanting or any of those things can be so joyous and also very quieting. We share and just say, ‘This is a way I comfort myself’.”

In a series of tweets before she died, Nancy, who was a production assistant on hit US TV show Glee, claimed Julia teased her about being overweight while she was growing up. She claimed her family had ­“abandoned” her and referring to Julia in January, she wrote: “Do you want to be a fan of someone so cruel? She’s not even that good of an actress. Just so you all know ‘America’s ­Sweetheart’ is a B***h!!”

Nancy and Julia had the same mother, Betty Lou, but different fathers. Julia’s dad was Walter Grady Roberts, who died of throat cancer, aged 44, in 1977, when she was just 10 years old.

Nancy’s father was Betty Lou’s second husband Michael.

Betty Lou claimed Michael was abusive and divorced him in 1983.

Julia, who won a Best Actress Academy Award for Erin Brockovich in 2000, missed a public ­memorial service for her half-sister last month. She reportedly held her own private farewell with close relatives.